Hacking the Lenco L-3808 turntable

As promised, I’ll let you know of some of the hacks I’ve used to try to get a better sound on my record deck. First you should read my previous article about the turntable. Some are more orthodox than others, some are cheap, some less so.

Isolating the Platform or the Feet

My turntable is on a slide-out shelf. It’s joined to the runners by four layers of velcro. This means that the platform is isolated from other vibrations in the room, but if I tap the shelf while a record is playing, you can see how important that is, the noise comes straight through the speakers. If you can’t isolate your shelf, you can maybe put some soft material under each of the feet. Some cork coasters should do the trick.

Replace the Felt Mat

You don’t need a slip mat, you need a GRIP mat. Slip mats are for DJs, not home listening. One really good material is Cork. But household cork tiles, used for insulation, can crumble. You have to seal them. A better alternative is rubberised cork. This involves a mixture of an artificial rubber (neoprene) and cork. You can get ready made mats of all kinds of materials but they can be expensive. It’s cheaper to buy neoprene cork (it’s used to make gaskets) and cut it yourself. The same goes for rubber sheeting.

At first, I ordered a rubber-cork mat, 1.5mm thick, it took a while to arrive, and when it did it was creased. Strangely enough, it’s so thin and flexible that when you put an LP on it, the weight of the record holds it flat! And certainly you notice that there is a small improvement in sound. It’s on the left and cost around £6.matsThe mat on the right was cut from a piece of nitrile rubber, 2mm thick, 300mm square, using the original felt mat and a piece of tailor’s chalk to mark it. It cost £4. You can use it on its own or with the cork mat on top of it. I cut the hole in the middle first, then used an old fashioned ball-point pen (BIC or Biro, they happen to be the right size) to keep the felt mat and the rubber concentric while I marked out the circle.

Since then, I bought two pieces of rubber-cork gasket, big enough to cut an LP size out of them.

The first was 1.5mm thick, and I also cut a large hole in the middle for the label area. Most LPs are fairly flat, but some have thicker labels. Singles are thicker in the middle, they have a ridge where they used to grip each other in old-style record players where  you stacked up the records. If you put this onto a flat turntable mat, you might find that the part of the record that plays isn’t flat on the mat. So I cut a large hole, 10.5cm (a little bigger than a record label), in the middle and glued it (using a gentle spray-glue, nothing that’s going to cause bumps) to the rubber mat above. I didn’t get the hole perfect, but that doesn’t matter, there’s nowhere near enough weight for it to upset the rotation of the platter. In the photo, there’s a bit of paper placed in the middle to illustrate that you can put some sort of decoration in the dip if you like! I’m looking for something better, suggestions welcome! (By the way, both cork mats are the same colour, why my phone found such a difference is beyond me!)

The second piece was 3mm thick, and I just cut an orthodox disc to the size of the original slipmat, with a 7mm hole in the centre.

mats2sLeft: 1.5mm rubberised cork on 2mm rubber. Right: 3mm rubberised cork

All the variations I tried were better than the supplied felt slipmat, but none were significantly better or worse than the other ones.

Reduce tonearm vibration

o-ringsIf you believe the hype, you will pay far more for a record deck without a tonearm, than one with, then pay even more again for a top quality tonearm. They say that if you stop the arm vibrating, and add some weight to it, you’ll get a better sound. Well there are ways to test that theory without spending a fortune, and that is to add some neoprene O-rings around the arm. I bought a pack of neoprene O-rings from a plumbing supplier. They sold them in tens, I had no other use for them, so I used all ten! Three at each end of the arm, and two pairs a third and two-thirds of the way along it. Size needed was 8mm internal diameter. Just over 2 quid. If reducing vibrations and increasing the weight of the arm brings about improvements, why not try it? It makes more sense than spending silly money.tonearm-with-oringsOf course, this might upset the not-very-accurate counterweight at the back of the tonearm and you need one of those scales to measure the stylus pressure (he had one in the video linked from the previous page). I waited a fair while for it to make its journey half way around the world. Thing is, you won’t need to use it more than once or twice, so go cheap!! I eventually found that with the arm set to 2 grams, the weight was actually 1.5g, and when I increased it to 2.5g, the actual weight was 2.14g. Which is where I’ve left it and it sounds just fine.

Get a Cartridge with an Elliptical Stylus

For the most part, Elliptical Styli are better than Conical type (round), such as the supplied Audio-Technica AT3600. The now discontinued Audio-Technica AT95E has a sound which is perceived by many to be one of the best at the low end of the market. I got one for £35, and a headshell for £6. I’m so glad I got it when I did, because they are getting hard to get hold of. It is possible to get a third party elliptical replacement stylus for the supplied AT3600 cartridge, but the market changes all the time. Like everything else, don’t go overboard with your spending. The AT3600 doesn’t sound bad, it just could be a touch better.

Try a different phono lead

Until recently, the more expensive Audio-Technica LP120 deck had a built-in phono lead hanging out the back. It was of the cheap variety, meaning that you couldn’t change it, or you had to open up the base and make internal changes to the deck. That’s been put right on newer models, but I’m glad that the Lenco didn’t have this problem. Changing the supplied lead for the one off my Pro-Ject turntable made a noticeable difference, and sometimes it sounded a lot better. However the lead wasn’t reliable, maybe a loose connection inside one of the plugs. It’s 12 years old!

I tried a couple of other leads, and some of them brought about really bad mains hum, even though they were designed for low-level phono signals (why else would, for example, the Kenable lead have an earth wire as well as two co-ax cables?).

I always understood that you need to keep the Ground connection separate from the cold wires from the cartridge. Not so. Inside the L-3808 the grounding and the two cold signal wires are connected together, and the only way to get hum is to use a poor quality stereo cable between the record deck and the phono pre-amp or phono input. I’m looking at you, Kenable!

I used the Pro-Ject lead, while I sorted out something new, and fortunately it stayed properly connected for the week or two until my other stuff arrived.

Try a different phono pre-amp

Meanwhile, I sent off for an Art DJ Pre ii phono pre-amp. It was well recommended on the internet, as something that punches well above its weight, which in this case was £50. art-preEven this can be improved if you plug a better power supply into it than the one provided. If you get upgrades from your internet provider, which include new modems, the old modem may be worthless by this time, but its power supply is often far better than the ones supplied with other items. And so it proved. Using the 1.5A 12V regulated supply from a long-discarded modem, instead of the ART one supplied, this pre-amp performs brilliantly. Being designed by Americans, it has a few bells and whistles that are not strictly necessary, and a power lamp that could do service in a lighthouse, necessitating a piece of black insulation tape, but it’s great!

Make a good quality lead

I sent off for some quality interconnect to join the record player to the pre-amp. I had four phono plugs of the screw-on type, which I’d bought a few years back and never used. They proved to be so good that I sent off for ten more, just in case! The interconnect was Van Damme branded, their pic makes it look like there’s an earth wire between the two channel wires, but that’s just a plastic spacer. And guess what, no hum whatsoever! The plugs were really cheap but they are good quality, if you can wait for them! I only used 70cm of the wire to make my phono lead, and here’s a spare one I made with the remaining 30cm when the plugs arrived. Two pairs of top drawer interconnects for a tenner.van-damme-leadOnce I had both the VanDamme lead and the Art-DJ unit in place, there was the biggest jump in sound quality of all the things I tried. There had been a big improvement using the Art-DJ unit compared to my old Behringer pre-amp, or the turntable’s built-in preamp, but together, with the Art-DJ and VanDamme lead together, records sound so much better.

Had I spent more money, say £250, on the AT-LP120 I would have still needed the improved phono pre-amp to benefit from it, and probably had to open up the unit to change the interconnect wire (though that’s no longer a problem on the latest ones). If I’d gone even higher, I’d definitely have needed a decent phono pre-amp because the costlier stuff doesn’t have one included, they assume you can afford one!

Some Sort of Conclusion

The costliest single upgrade I made was the Art-DJ preamp, and had I spent more on a record deck, I’d have needed to do this anyway, possibly even more money to match the potential of the record deck. With some decks I might have to have opened them up to improve the phono lead. Perhaps I wouldn’t have needed the cartridge upgrade, who knows? But the biggest amount of fun is trying out the other really cheap tweaks to squeeze a little extra tightness to the sound.

Other things worth trying

You can try lining the underside of the platter with modelling clay to make it heavier. You can even add some inside the unit if you want to open it up. Just wait until your guarantee has expired before you do the latter!

Where to spend your money

Of course, on records! Whatever you spend on your turntable, make sure you have enough left to buy records else it’s all fairly pointless. And the main thing, have fun!

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